Consider move-to-front as opening to finish recents

There can be multiple transient-hide tasks (i.e. mPausingTasks).
Such as entering recents from a translucent task, then all
visible tasks will be transient-hide.

It is possible to choose a non-top visible task as the target
to return, then the task will be CHANGE mode with FLAG_MOVED_TO_TOP.
Then the operation (merge) should open the task (leave recents)
instead of doing nothing.

Bug: 313596094
Test: Launch Task A, launch translucent task B.
      Swipe up to enter recents. Click the TaskView of Task A.
      The recents should be closed and go to Task A.
Change-Id: I6462b5d8b2b8658dba6190a01b75dd58edf6ee7f